encguide – Documentation of LaTeX font encodings

The doc­u­ment dis­cusses the con­cepts be­hind, and the re­stric­tions
that af­fect LaTeX's use of font en­cod­ings. The doc­u­ment also
lists sev­eral ex­tant ‘recog­nised’ en­cod­ings,
giv­ing glyph ta­bles for them.